To celebrate their wedding anniversary, Derek and Lucy decided to spend the night out on the town. After dinner, which incidentally cost them one-third of the money they had brought with them, they purchased two theater tickets at $9.80 each. After the show, they spent one-fourth of their remaining bankroll for a taxi ride around the city. They then went to get desserts, where their total cab came to $23.10. The cab fare home cost them one-half of their remaining money. After they had tippled the driver a dollar, they had $4.10. How much did their celebration cost them?

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